Incidence of new-onset type 1 diabetes during Covid-19 pandemic: A French nationwide population-based study

AIM: The association between infection with SARS-CoV-2 and the development of new-onset type 1 diabetes mellitus (T1DM) is unclear. The aim of this study was to examine the impact of the Covid-19 pandemic on the hospitalization rates for new-onset T1DM and diabetic ketoacidosis at diagnosis, in metropolitan France. METHODS: This nationwide retrospective cohort study included hospital data on all patients aged 1 to 35 years old, hospitalized in France due to onset of T1DM, in 2020 and 2021 compared to 2019. RESULTS: Apart from a decrease during the lockdown in 2020, the number of hospitalizations due to new-onset T1DM was not significantly different in 2020 and 2021 than it was in 2019. In the regions most affected by Covid-19 and covering 7,995,449 inhabitants aged from 1 to 35 years old, standardized hospitalization rates were not significantly different in 2020 and in 2021 compared with 2019. The number of hospitalizations for diabetic ketoacidosis at diagnosis was not significantly different after week 14 in 2020 and in 2021 compared with 2019. CONCLUSION: In this nationwide study, the incidence of hospitalizations for new-onset T1DM and the incidence of diabetic ketoacidosis at diagnosis was not increased during the Covid-19 pandemic in 2020 and 2021. Our results support the fact that infection with SARS-CoV-2 does not promote the development of T1DM.